Brown Recluse Spiders

Facts, Identification & Control

Latin Name

Loxosceles reclusa

Appearance / Identification

What Does a Brown Recluse Spider Look Like?

Brown Recluse Spider Illustration

Adult specimens vary in color from dull yellow to tawny, dark brown. Younger spiders are lighter in color than adults. The abdomen of the brown recluse has no stripes or spots. Adults measure approximately 6 to 11 mm in length of body. At the widest leg span, their bodies are roughly the size of a United States quarter.

The most telltale characteristic of brown recluse spiders is the presence of a dark, violin-shaped mark on the dorsum of the arachnid’s light brown or yellowish-brown cephalothorax. The neck of this distinct violin pattern is directed toward the abdomen. Due to this marking, brown recluses are also commonly known as fiddle-back spiders. To positively identify a spider as a recluse, both the eyes and fiddle marking must be seen, since other spiders may possess one or the other characteristic alone.

brown recluse image
Brown Recluse Spider

Behavior, Diet & Habits

Brown recluse spiders dwell in dark, sheltered places and can be found in homes, barns and basements. Webs tend to appear disorganized and are built most commonly near ground level. The spider is a hunter, so the web is not intended to catch prey but instead roams around searching for prey. The brown recluse is found in the central southern part of the U.S., from Texas to the western most part of Florida.

Brown recluse spiders are shy and rarely bite unless provoked. Bites usually go unnoticed until effects manifest a few hours later. Most bites become red and fade away, but in uncommon cases necrosis or tissue damage can occur. A medical professional should be consulted if there are medical concerns.

Reproduction

Female brown recluses generate one to five egg sacs which can contain 31-300 eggs.  Eggs usually hatch in about a month.  Development from egg to adult is approximately a year.

Young brown recluse spiders are slow to grow and may reach maturity within 10 to 12 months. Their development is influenced by factors such as food and weather conditions. However, brown recluse specimens are capable of surviving for extended periods without food or water.

Signs of a Brown Recluse Spider Infestation

The most likely sign of recluses are sightings of the spider.

More Information

Although urban myth purports that they are found throughout the U.S., studies have shown otherwise. Brown recluse spiders are endemic only to the American South and Midwest. Relocation of the brown recluse can occur in boxes or items moved from its native range. These usually are isolated events and do not result in an entire area becoming infested.

Many conditions are mistakenly diagnosed as brown recluse spider bites, including Lyme disease, diabetic ulcers, reactions to medication and bacterial infections.

Due to misinformation and fright, many people identify harmless spiders as brown recluses. They are also referred to as fiddleback spiders due to a distinctive marking on the thorax, which resembles a violin. Brown recluses have uniformly colored legs and abdomens; so any spider exhibiting distinct color variations and patterning on the legs or abdomen is not a brown recluse.

More Pictures close-up of brown recluse spider

brown recluse spider

Brown Recluse Spider Bite

Where Do Brown Recluse Spiders Live?

How Strong is a Brown Recluse Spider Web?